That's reminded me, has my project been assessed yet please John?
I dropped it off at the end of June, did the exam in March.
Also, it looks like I'll be doing your PAT course between Christmas and New Year, would that still be going ahead if only a few register?
(or maybe it is a busy week, where anyone who works is able to get to you?)
Thanks
Alan.

i have just started my time off work, in which i hope to get the project done and handed in. i did the exam last May (2012) but due to working away and then travelling around australia (has been booked for 4 years) time is ticking fast before the 12months limit we were given runs out, so i am locking myself away for a week or so and trying get it sorted. i am trying to pick up where i left off, i just hope i dont go into too much detail that wastes time for no real gain.

what is the avearge people have spent from start to finish on the project??the 40hrs seems very optimistic

Certainly most people I know who have undertaken the project have spent about 120 hours on it - and probably about another 40 or so making mid course corrections when elements of the initial design solution have proved challenging in practical design - typically things like grouping factors when faced with a single tray or trunking run are difficult to resolve so a multiple run approach then required takes quite a bit of re design effort (drawings, circuit lengths and containment sizes then all have to change. Equally, "circuiting up" causes a few dramas when doing the lighting in terms of circuit load and probable phase allocation.

There are loads of areas where either a lack of design experiece or access to your tutors causes a lot of work that's "abortive".

Equally, you should also look for "similarity" betwen aspects of the questions - helps you avoid producing two sets of calculations showing similar things when one set showing everything is easier - spreadsheets are ideal for this task as you can selct what you want to produce from a single "model".

Remember that design is iterative - you go so far, hit a problem, make corrections and recycle it into a new solution - that's where the time goes.

Look at your grouping factors and do not go below 50%. In my case that meant confining myself to about 8 circuits per lump of trunking.

Diversity, Diversity, Diversity.

I smiled my way into Argos with a Clamp meter. Went home and diversified some more.

You can do it.

Zs

Edit: Gary, Are you working on Johnston's Catalogue shop? I thought that had expired and been replaced so i doubt it. I will not give you any answers because that is not fair on those of us who cracked on in an OMS stylee (ref the funky new avatar) and presented on time and did it on our own, but I will give you some helpul googles to save you some time, in public. If you are stuck, then move on to the perifery questions and get googling as a break from the circuit questions.

Google 10kW PV array, Shropshire, and PV array calculator. I have just given you a present.

I haven't seen this project, there are probably a few circuits that are loaded at less than 30% of their grouped current rating and therefore can be ignored from the overall grouping factor as per note 9 from table 4C1.

I haven't seen this project, there are probably a few circuits that are loaded at less than 30% of their grouped current rating and therefore can be ignored from the overall grouping factor as per note 9 from table 4C1.

Regards

That's the skill of the designer to ensure that selected circuits don't exceed 30% of grouped rating - particularly lighting circuits when contrasted against mitigating inrush current operation of CPD's.

I'm not sure if this is offered by tutors, but certainly it doesn't come naturally to the candidates - although with a bit of prompting the mists clear and, when the rationale is understaood, it saves hours of grief for the candidate

I haven't seen this project, there are probably a few circuits that are loaded at less than 30% of their grouped current rating and therefore can be ignored from the overall grouping factor as per note 9 from table 4C1.

Regards

That's the skill of the designer to ensure that selected circuits don't exceed 30% of grouped rating - particularly lighting circuits when contrasted against mitigating inrush current operation of CPD's.

I'm not sure if this is offered by tutors, but certainly it doesn't come naturally to the candidates - although with a bit of prompting the mists clear and, when the rationale is understaood, it saves hours of grief for the candidate [IMG][/IMG]

Regards

OMS

And there's also non-simultaneous overload, which seems to be quite common in B&D world.

Finished task A and c but task b the only question i have not done is about PV installation how much in depth have you got to look into it.

Well as the exam is an exercise in BS 7671, then concentrate on that bit - look at various guidance notes that discuss small scale embedded generation

Understand the basic implications of what 10kW means in terms of current and what impact that has on DNO agreement to connect to networks - can it be made much simpler if you take an alternative approach. How bick would a 10kW array be - if you stick it on the roof will there be impacts on bonding for your TN-C-S system and or lightning protection systems

Hi all. Been reading a lot of topics in regards to grouping factors, none of which seem to have the exact answer I'm looking for.

I'm currently in the process of doing a project for my 2396 Design & Verification course which is a 2 storey college block. I'm using metal trunking (method B) and pvc 70ºc singles (Table 4D1). There are 3 runs of trunking which encompass the whole building, 2 for the ground floor, and 1 which rises to the 1st floor. My grouping factors are 0.47 (11 circuits) for both of the ground floor runs, and 0.43 (14 circuits) for the 1st floor run.

After doing all of my Lighting circuits, I came to the Power calculations. Obviously, these grouping factors applied to a 20a Ib (or In) produces ridiculously high Iz (or It) figures (10mm to be precise).

"Use Note 9", I hear you say... Well, even after changing all of my lighting circuits to 2.5mm, only 6 circuits were lightly loaded (2 on each run) Thanks to the Guilds for making the majority of the lighting fluorescent/discharge with a 1.8 factor.

As the drawings merely show twin s/o's, I have no idea what the actual uses are for each circuit, and I would actually prefer to use the correct figures found in the Regs.

The only solution I can see is changing all of my containment to either add another trunking, or a completely different installation method. But seeing as I've had these all printed out on A1 scaled drawings, I'm a bit reluctant to do so. Also having worked on site for 4 years or so, I (and no doubt every other commercial/industrial spark) have seen trunking runs stuffed to the brim. Something just doesn't add up!

As sympathetic as it was, I didn't see any real solution in your reply Andy. There seems to be a lot of people discussing the 2396 project in this thread, so it seemed appropriate to post the message here also.